Plug removing tool



Sept. 20, 1938. R. K, HOPKINS PLUG REMOVING TOOL Filed June 27, 1936 Patented Sept. 29, 1938 'ETES rarer or ies The M. W. Kellogg (30., New York, N. Y, a

corporation of Delaware Application June 27,

Claims.

This invention relates in general to pipe headers of the type used to form pipe coils for the petroleum refinery and kindred arts and more particularly to a plug pulling device for pulling the plugs of such pipe headers.

Pipe coils of the character used for heating fluids in the chemical, petroleum refinery and kindred arts usually comprise a plurality of pipe lengths whose ends are expanded or otherwise fastened to pipe headers to form the desired flow path or flow paths. The pipe headers may be of various forms but they generally include a metal body provided with two or more holes into which may be expanded the ends of a proper number of pipes. Opposite each of the holes is provided a plug seat upon which is adapted to seat a removable plug. Suitable arrangements are also provided to hold the plugs on their seats during use of the coil. Because of the character of the fluids passed through the coils, and the extremely high temperatures and pressures of the fluids, the fit between the plugs and their seats is very close and considerable pressure is exerted on the plugs by the plug holding arrangements to assure a 25, leak-proof construction.

The removal of the plugs from their seats for inspection and/or cleaning of the coils is a troublesome task at best, as the headers are generally so closely nested that there is not very much room 1 to get at the plugs with the usual tools. The task is particularly troublesome when the fluid is petroleum or a petroleum product as these materials have a tendency to form coke in the headers which generally binds the plugs to their seats. When the plugs bind on their seats, it is difficult to remove them without damaging either the plugs or their seats. When either the plugs or their seats are damaged expensive repairs are necessary in order to again obtain a fluid tight seal.

It is an object of this invention to provide a simple and rugged device for removing plugs from headers of the character mentioned which will remove plugs quickly and easily and without damage to the plugs or the plug seats; the device furthermore being such that it can be used successfully even when the headers are nested together on short center to center distances.

The further objects and advantages of the invention will be readily apparent from a consideration of the following description of a preferred embodiment thereof taken with the accompanying drawing, in which,

Fig. l is an isometric view of an assembled header, of which parts of the walls are removed 1936, Serial No. 87,685

to better show the internal structure, in which the novel plug pulling device is mounted preparatory to unseating the plug,

Fig. 2 is a view similar to Fig. 1 but showing the plug pulling device as it appears after the plug is unseated,

Fig. 3 is a front view of the plug pulling device,

Fig. 4 is a side view of the plug pulling device,

Fig. 5 is a front view of a header plug, and

Fig. 6 is a sectional view of a header set collar.

The plug pulling device of the invention may be used in combination with pipe headers of various forms and design. For the purposes of this specification I choose to disclose the plug pulling device of the invention in combination with the pipe header it shown in the drawing. The pipe header H3 shown is a two-hole header, but it should be obvious that this is illustrative only and that header H3 may have any number of holes.

Header iii includes an H shaped body that is made up of two hollow cylindrical portions H and I2 that are integrally connected by a hollow cross-over member 53. Cylindrical portions H and I2 each have one end appropriately machined to provide tube seats it into which may be rolled, or otherwise expanded, the ends of their tubes, not shown, of the pipe coil, also not shown.

Cylindrical portions H and 52 have plug seats l5 formed therein. Seats it are located in the other end of cylindrical portions H and I2 adjacent the top of the passageway in cross-over member l3. Plugs 56 are adapted to seat on plug seats l5 and are held in fluid tight relation thereon by the pressure exerted through set collars H. Plugs it may have substantially flat bottoms as shown, or they may be of the deflector type. In the latter case suitable arrangements are provided for assuring the proper orientation of the plug on the plug seats.

As best shown in Fig. 5, plug 16 includes a body portion i8 from which extends a shank i9. Shank 19 may be formed integral with body portion it as shown, or it may be formed as a separate piece and united to body portion 68 in any suitable manner as by a screw threading, etc. The end of shank i9 is threaded to receive nut 26. The side of body portion 58 is tapered to seat accurately on plug seat 55. The top of body portion I8 is also tapered to present a conical surface 2! that is adapted to seat on a conical surface 22 formed in the bottom of set collar ll.

Set collars I! have a central hole through which may pass shanks l9 and are threaded on the outside so that they may be screwed into the tapped ends of cylindrical portions II and I2. The ends of set collars I'I that extend from header II] are screwed into nuts 23 so that a wrench or other suitable tool may be used in tightening them against the conical surfaces 2| of plugs I8. When set collar I1 is thus tightened, surfaces 2| and 22 coact to center plug I6 as well as to force it into fiuid tight relation with its seat I5.

The plug puller 25, as best shown in Figs. 1, 2, 3 and 4, includes a bifurcated wedge 26 that terminates at one end in an anvil block 21. The top face of anvil block 2'! presents an inclined face so that it may conveniently be struck at an angle with a hammer or other tool. The open space between the tines 29 and 30 is made of a width sufiiciently greater than the diameter of shank I9 to allow wedge 26 to be easily slipped over shank I9 for the plug pulling operation. Tines 23 and 39 are provided respectively with blocks 3| and 32 at their ends; Blocks 3| and 32 serve to stop the downward movement of plates 33 and 34. Anvil block 21 has a hole therein into which passes the reduced end of bent bar 35. Bar 35 is held in position in anvil block 21 by means of a pin 36. The outside edges of each of tines 29 and 30 are provided with V-shaped tongues 31 which are adapted to fit in V-shaped grooves in plates 33 and 34. It is of course obvious that tongues 31 and their cooperating grooves need not be V-shaped as shown, but may be of any preferred shape.

Plates 33 and 34 are images of one another. Each of plates 33 and 34, when positioned on wedge 26, has an inside face that is substantially parallel to a face of wedge 26 and an outside face that is substantially parallel to a plane passing through the middle of wedge 26. Plates 33 and 34 are made wider than wedge 26 so as to provide V-shaped shoulders 38 that define the V-shape-d grooves in which V-shaped tongues 31 are accommodated. Plates 33 and 34 are provided with central slots of substantially the same width as the space between the tines 29 and 30. Plates 33 and 34 are made only a little more than half as long as wedge 26 so as to obtain substantial separation of them when they are moved from one end of the wedge to the other. The ends of plates 33 and 34 adjacent blocks 3| and 32 are cut away to eliminate sharp corners and to facilitate positioning of plug puller 25 between nut 23 and set collar I'I.

To assemble plug puller 25 the grooves of plates 33 and 34 are made to register with the tongues 31 of wedge 26 and then moved on wedge 26 towards blocks 3| and 32. The reduced end of bent bar 35 is then passed into the hole in anvil block 2'! and fastened thereto by inserting pin 36 in place. After this is done plates 33 and 34 cannot be removed from engagement with wedge 26 as rod 35 limits their movement in one direction and blocks 3| and 32 limit their movement in the other direction.

To pull plug I6, set collar I1 is turned by means of a wrench, or suitable tool, until it is spaced from nut 28 by a distance a little greater than the distance separating the parallel faces of plates 33 and 34 when plates 33 and 34 are abutting blocks 3| and 32 as shown in Fig. 1 and in dotted lines in Figs. 3 and 4. Plug puller 25 is then raised over shank I9 and slipped in position as shown in Fig. 1. Plug puller 25 is handled by grasping bar 35. This automatically assures plates 33 and 34 being properly positioned as their weight is sufficient to cause them to move down on wedge 26 until they contact blocks 3| and 32.

In many cases the weight of wedge 26 is enough to cause it to move down between plates 33 and 34 with sufficient force to pull plug I6 off seat I5. However, when plug I6 is frozen to its seat I5, as usually happens when there is a considerable deposit of coke in header II], it is necessary to exert a greater force. This is accomplished by striking anvil block 21 a sharp blow with a hamber or other tool. The hammer blow will cause a separation of plates 33 and 34 and the pulling of plug I6. The plug pulling device 25 is particularly efiicacious for the reason that the hammer blow does not merely set up a force tending to pull shank I9 longitudinally, but also sets up a force which tends to move shank I9 downwardly at its outer end. The resultant of these forces tends to pull plug I6 angularly off its seat. The deviation of the resultant force from the axis of shank I9 is small and consequently no harm is done to the plug I6 or its seat I5.

It is to be noted that by reason of the curved surface presented by anvil block 21 the anvil block 2! may easily be struck by a hammer or the like when even close spacing of header I6 is employed. However if the spacing should be so close that anvil block 21 cannot be struck without danger of striking a header III or a shank I9 above it the desired operation is obtained nevertheless by striking bent bar 35.

While a preferred embodiment of the invention has been shown and described it is to be understood that the invention is not limited thereto but that it includes all modifications and variations falling within the scope of the ap pended claims.

I claim:

1. A plug pulling device of the character described comprising a pair of complementary members having substantially parallel outside faces, a bifurcated wedge member movable between said complementary members having a central slot therein that terminates adjacent the larger end of said Wedge member, each of said complementary members having an inside face substantially parallel with the adjacent face of said wedge member and being bifurcated to provide a central slot adapted to register in width with the slot in said wedge member, means adjacent each end of said wedge member limiting the relative movement between said wedge mem her and said complementary members, and undercut means in said wedge member and said complementary members to hold said wedge member between said complementary members.

2. A plug pulling device of the character described comprising a pair of complementary members having substantially parallel outside faces, a bifurcated wedge member movable between said complementary members having a central slot therein that terminates adjacent the larger end of said wedge member, each of said complementary members being substantially shorter than said wedge member, each of said complementary members having an inside face substantially parallel with the adjacent face of said wedge member and being bifurcated to provide a central slot adapted to register in width with the slot in said wedge member, means attached to the end of each tine of said wedge member limiting the relative movement between said wedge member and said complementary members, an anvil member at the larger end of wedge member having an inclined top face, limiting means in said anvil memberadapted to limit the relative movement between said wedge member and said complementary members, and undercut means in said complementary members and said Wedge member to hold said Wedge member between said complementary members.

3. A plug pulling device of the character described comprising a pair of opposed complementary members, each of said members being generally U-shaped to provide a central slot extending for a substantial portion of the length thereof and having an outside face disposed substantially parallel to the corresponding face of the other member, a bifurcated wedge movable between said members of a length exceeding that of said members, said members each having an inside face disposed parallel to the adjacent face of said wedge, the central slot of said wedge being longer than the slots of said members and being adapted to register with said slots, undercut means in said wedge and members adapted to hold said Wedge and members in engagement, a stop block at the end of each tine of said wedge to limit the movement of said wedge relative to said members in one direction, and a removable member insertable in said Wedge adjacent the larger end of said wedge and extending into the path of both of said members adapted to limit the movement of said wedge relative to said members in another direction and to prevent removal of said members from engagement with said wedge while it is inserted in said wedge.

4. A plug pulling device of the character described comprising a pair of opposed complementary members, each of said members being generally U-shaped to provide a central slot extending for a substantial portion of the length thereof and having an outside face disposed substantially parallel to the corresponding face of the other member, a bifurcated wedge movable between said members of a length exceeding that of said members, said members each having an inside face disposed parallel to the adjacent face of said wedge, the central slot of said wedge being longer than the slots of said members and being adapted to register with said slots, undercut means in said wedge and members adapted to hold said wedge and members in engagement, a stop block at the end of each tine of said wedge to limit the movement of said wedge relative to said members in one direction, an anvil block having an outwardly inclined impact face at the larger end of said wedge, and a removable member insertable in said block adjacent the larger end of said wedge and extending into the path of both of said complementary members to limit the movement of said Wedge relative to said complementary members in another direction and to prevent removal of said complementary members from engagement with said wedge While it is inserted in said anvil block.

5. A plug pulling device of the character described comprising a pair of opposed complementary members, each of said members being of generally triangular cross section and U- shaped to provide a central slot extending for a substantial portion of the length thereof and having an outside face disposed substantially parallel to the corresponding outside face of the other member, the outside corner of each branch of the Us being cut away to facilitate the insertion of said substantially parallel faces between surfaces to be separated by the plug pulling device, a bifurcated wedge movable between said members of a length exceeding that of said members, said members each having an inside face disposed parallel to the adjacent face of said wedge, the tines of said wedge having their inner corners removed to facilitate positioning of said wedge for use, undercut means formed in said wedge and members adapted to hold said wedge and members in engagement, a stop block at the end of each tine of said wedge in the path of said members, an anvil block at the larger end of said wedge having an inclined top, and a bent member insertable in said block and extending into the paths of said members.

ROBERT K. HOPKINS. 

